1. RV Roof Repair
  2. Alpha Systems
  3. Sealant
  4. White
  5. 9.8 Oz
Alpha Systems AlphaThane 5121 Self-Leveling Sealant for RVs - White - 9.8 oz - Qty 1

Alpha Systems AlphaThane 5121 Self-Leveling Sealant for RVs - White - 9.8 oz - Qty 1

Item # AL35KV
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RV Roof Repair AL35KV - 9.8 Oz - Alpha Systems
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Seal the skylights, vents, and other horizontal surfaces of your RV roof with this self-leveling sealant. Strong, weather-resistant formula works with wood, metal, and glass. Sealant has a longer lifespan and remains flexible for RV travel. Lowest Prices for the best rv roof repair from Alpha Systems. Alpha Systems AlphaThane 5121 Self-Leveling Sealant for RVs - White - 9.8 oz - Qty 1 part number AL35KV can be ordered online at etrailer.com or call 800-298-1624 for expert service.
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Alpha Systems RV Roof Repair - AL35KV

  • Sealant
  • White
  • Alpha Systems
  • 9.8 Oz

Seal the skylights, vents, and other horizontal surfaces of your RV roof with this self-leveling sealant. Strong, weather-resistant formula works with wood, metal, and glass. Sealant has a longer lifespan and remains flexible for RV travel.


  • Self-leveling sealant seals the roof membrane edges, skylights, vents, and other horizontal surfaces of your RV
    • Adheres to wood, metal, and glass
    • Self-leveling settles for a low-profile seam
  • Rubber-based formula provides a weather-resistant, flexible seal
    • High solid concentration for a longer lifespan
    • Low VOC means less air pollution
    • Remains flexible for the movement of RV travel
  • Longer dry time is best for fine touches and proper tooling - 48 hours, then ready for the road
    • Applies with a standard caulking gun
    • Can be painted once cured
  • White color matches your RV
  • Made in the USA


  • Coverage: 30' at 1/4" bead
  • Viscosity: 45,000 - 60,000 centipoise
  • Shelf life: 12 months
  • Quantity: (1) 9.8 oz tube

Note: Keep away from sparks, heat, and open flame. Overexposure can cause nausea. Ideal for use on the exterior of your RV. If used indoors, make sure are is well ventilated until sealant fully cures

RV Sealant - Non-Sag vs Self-Leveling

The kind of sealant you apply to your RV is important. To determine the type of sealant you need for your application, you will want to consider what it is you are sealing and where it is on your RV.

Self-leveling sealant is designed to level out as you apply it. The thick liquid slowly flows into a level position as gravity takes effect. This is particularly useful when sealing flat surfaces, like around a roof vent, AC, or skylight. As you apply the sealant, gravity will cause it to settle into an even line, giving you a clean, low-profile look.

Non-sag sealant is designed to retain its shape as you apply it. The consistency of the liquid is thick but malleable enough to be easily applied without causing sagging or slumping. This is useful when sealing vertical surfaces, such as the edges of a wall, window, or vent. As you apply the sealant, it will harden just enough to keep the liquid from drooping, giving you a clean, even look.

AlphaThane 100% solids

Alpha System's AlphaThane sealants are formulated with 100% solids. This prevents the sealant from shrinking as it cures, making it an ideal choice if your job requires filling larger gaps.

AlphaThane 5121 self-leveling sealant is weather resistant and suited for outdoor applications. Gloves and safety glasses are recommended for installation. Respiratory protection recommended if used indoors.

862215 Alpha Systems MS Polymer Sealant 5160 - White - 9.8 oz

Video of Alpha Systems AlphaThane 5121 Self-Leveling Sealant for RVs - White - 9.8 oz - Qty 1

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Review of Alpha Systems RV Roof Repair - White- Self-Leveling Sealant - AL35KV

Michael: Hi there, I'm Michael with etrailer.com. Today, we're going to take a quick look at the Alpha Systems MS polymer sealant. This is a self-leveling sealant. So it's going to be great for working on your RV roof. Maybe if you just put down a new roof, you're wanting to put all of your air conditioning and vents back in place, or if you're just replacing any of those components, you want a self-leveling sealant like this. When you put your bead down, it is going to gradually spread out to make sure that you have a nice seal cover over all of your components so you don't have to worry about rain water getting, or anything like that.

So this is going to be for your level flat surfaces. It's not going to be for your vertical surfaces. So if you're putting in a window or a door or something like that, you're going to want non sag. That's a different product, but that holds its shape. It doesn't run down like this would.

So just be sure that you're getting the right sealant for your application.This is an MS polymer, so it's going to be great. It's got modified silicone, so it's very strong, durable. It's got a tensile strength of 225 PSI, pounds per square inch. So if you're wanting to have something that's going to hold up well, give you that nice level seal and give you a lot of durability, this is going to be a great option for you. This can be used indoors or outdoors.

So if you do have something inside that's going to have a level surface to it, you can use it inside as well.This is the white option. It does come in four different colors. So you can have a white, almond, beige or gray. I do want to show you some of those other options as well, so that you can see the difference between the almond and the beige specifically. So you can see with the labels up here, the almond is more like a light tan kind of color.

The beige has more gray in it, so it's like a mix between the gray and the almond, and then your gray doesn't have very many warm tonalities to it at all. It's kind of de-saturated. So depending on what your roof membrane or whatever your application is that you're applying this to, that will determine the color that you want, but we do have all four options here at etrailer.com.All of these are going to be your 9.8 ounce size so they're going to do a good job. I would say that you'd probably be able to do like a whole air conditioning system, putting one in with one of these tubes. So depending on how many vents and things that you're planning on putting in, will determine how much that you need. Now, these can be applied with your standard caulk gun, they include the nozzle here that just screws in place like I just did, so that you can easily use the caulk gun to run this along. You can also use a trowel or a stiff brush to apply it.It is made in the USA, so you can trust it's made to the high quality standards that we've come to know and trust for products made here in the US. I think it's going to do a really good job for you. It takes about 15 minutes to set up. The tack-free time is about 15 minutes so not very long at all, but it is self leveling so you do want to give it some time to settle in and to set up before you drive down the road or anything, or get it wet. So it is a good idea to install it on a nice dry day with a clean surface to make sure that everything is going to adhere properly. So if you're looking for a self-leveling sealant, I think this is going to be a great option for you. And we do have all four colors to match your setup. So that's going to complete our look for today. Again, I'm Michael with etrailer.com. Thanks for watching.


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Info for this part was:

Employee Amanda M
Edited by:
Amanda M
Employee Halie H
Written by:
Halie H
Employee Michael B
Installed by:
Michael B
Employee Eric H
Updated by:
Eric H

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